At least 7,000 species and subspecies of indigenous US flora have been categorized. The eastern forests contain a mixture of softwoods and hardwoods that includes pine, oak, maple, spruce, beech, birch, hemlock, walnut, gum, and hickory. The central hardwood forest, which originally stretched unbroken from Cape Cod to Texas and northwest to Minnesota supports oak, hickory, ash, maple, and walnut. Pine, hickory, tupelo, pecan, gum, birch, and sycamore are found in the southern forest that stretches along the Gulf coast into the eastern half of Texas. The Pacific forest is the most spectacular of all because of its enormous redwoods and Douglas firs. In the southwest are saguaro (giant cactus), yucca, candlewood, and the Joshua tree. The central grasslands lie in the interior of the continent, where the moisture is not sufficient to support the growth of large forests. Tall grass covers large portions of the coastal regions of Texas and Louisiana and occurs in some parts of Mississippi, Alabama, and Florida. The Pacific grassland includes northern Idaho, the higher plateaus of eastern Washington and Oregon, and the mountain valleys of California. The intermontane region of the Western Cordillera is for the most part covered with desert shrubs. The lower slopes of the mountains running up to the coastline of Alaska are covered with coniferous forests as far north as the Seward Peninsula. The central part of the Yukon Basin is also a region of softwood forests. Hawaii has extensive forests of bamboo and ferns. Sugarcane and pineapple, although not native to the islands, now cover a large portion of the cultivated land. Small trees and shrubs common to most of the United States include hackberry, hawthorn, serviceberry, blackberry, wild cherry, dogwood, and snowberry. An estimated 432 species of mammals characterize the animal life of the continental United States. Among the larger game animals are the white-tailed deer, moose, pronghorn antelope, bighorn sheep, mountain goat, black bear, and grizzly bear. Some 25 important furbearers are common, including the muskrat, red and gray foxes, mink, raccoon, beaver, opossum, striped skunk, woodchuck, common cottontail, snowshoe hare, and various squirrels. Human encroachment has transformed the mammalian habitat over the last two centuries. The American buffalo (bison), millions of which once roamed the plains, is now found only on select reserves. Other mammals, such as the elk and gray wolf, have been restricted to much smaller ranges. Year-round and migratory birds abound. Lakes, rivers, and streams teem with trout, bass, perch, muskellunge, carp, catfish, and pike; sea bass, cod, snapper, and flounder are abundant along the coasts, along with such shellfish as lobster, shrimp, clams, oysters, and mussels. Four poisonous snakes survive, of which the rattlesnake is the most common. Alligators appear in southern waterways and the Gila monster makes its home in the Southwest. Laws and lists designed to protect threatened and endangered flora and fauna have been adopted throughout the United States.
Fauna and flora
At least 7,000 species and subspecies of indigenous US flora have been categorized. The eastern forests contain a mixture of softwoods and hardwoods that includes pine, oak, maple, spruce, beech, birch, hemlock, walnut, gum, and hickory. The central hardwood forest, which originally stretched unbroken from Cape Cod to Texas and northwest to Minnesota supports oak, hickory, ash, maple, and walnut. Pine, hickory, tupelo, pecan, gum, birch, and sycamore are found in the southern forest that stretches along the Gulf coast into the eastern half of Texas. The Pacific forest is the most spectacular of all because of its enormous redwoods and Douglas firs. In the southwest are saguaro (giant cactus), yucca, candlewood, and the Joshua tree. The central grasslands lie in the interior of the continent, where the moisture is not sufficient to support the growth of large forests. Tall grass covers large portions of the coastal regions of Texas and Louisiana and occurs in some parts of Mississippi, Alabama, and Florida. The Pacific grassland includes northern Idaho, the higher plateaus of eastern Washington and Oregon, and the mountain valleys of California. The intermontane region of the Western Cordillera is for the most part covered with desert shrubs. The lower slopes of the mountains running up to the coastline of Alaska are covered with coniferous forests as far north as the Seward Peninsula. The central part of the Yukon Basin is also a region of softwood forests. Hawaii has extensive forests of bamboo and ferns. Sugarcane and pineapple, although not native to the islands, now cover a large portion of the cultivated land. Small trees and shrubs common to most of the United States include hackberry, hawthorn, serviceberry, blackberry, wild cherry, dogwood, and snowberry. An estimated 432 species of mammals characterize the animal life of the continental United States. Among the larger game animals are the white-tailed deer, moose, pronghorn antelope, bighorn sheep, mountain goat, black bear, and grizzly bear. Some 25 important furbearers are common, including the muskrat, red and gray foxes, mink, raccoon, beaver, opossum, striped skunk, woodchuck, common cottontail,Link to the american fauna and flora
Exercises
American geography